gmforlife

iTrader: (2)

First off, i'm sure this has been discussed before but my computer is pretty slow and i did search but didn't come up with the answer i am looking for. So, i'm looking into doing a project using a 2005 d-max LLY and i have a couple questions on that. I would like to know what the difference between the LLY and the LMM motor. Are they or are they not the same exact setup mechanically? Is it just the tune? Because i know they have a decent difference in power, and i've never really got heavy into diesel tuning. Can the tunes just be copied over from one to the other and have them produce the same if not close to the same power numbers?

The reason i'm asking this is because i want to use a d-max motor out of an EXPRESS VAN, and those are the LMM motors with a 4l80 tranny, now my thinking is they detune it because that 4l80 doesn't hold as much power as the Allison. But the project needs a smaller transmission, and considering i could get a d-max 4l80 for much cheaper through an express van, i would like to know if it's all in tuning, therefore i can make up that hp difference.

Also, since they did use the 4l80 with a d-max, the computer, is that a d-max pcm? Is the operating system completely different compared to a truck? Obviously nobody posts on HPTuners Express Van tunes because nobody mods them, haha. So any answers would be greatly appreciated.

Zick

iTrader: (18)

The LMM engine is more like the 2006-2007 LLY/LBZ than it is like the 2005 LLY.

They redesigned the 6.6 in 2006 for the LLY/LBZ which makes it different than the 2005 LLY engine. They only different between the LLY & LBZ is the programming.

http://www.dieselplace.com/forum/showthread.php?t=67521

gmforlife

iTrader: (2)

So i could run an LLY/LBZ tune in an LMM and it should run fine? Thanks for all the info bro.

Zick

iTrader: (18)

Why would you try and run the LLY or LBZ tune in the LMM?
The LMM is newer and I really have no idea if it will run on the LBZ tune. I'm not sure if the PCM's are even the same.

gmforlife

iTrader: (2)

Well, a buddy of mine tells me that he want to do a d-max project in his truck, but he can get the d-max and 4l80 out of the EXPRESS VANS, and it's cheaper than buying a new truck. He tells me that the d-max motor that comes in the vans are the DE-TUNED LMM motor, don't know if that is correct or not. I would imagine the do de-tune it because it is back up by a 4l80 not an allison. So he wants to build up the 4l80 and run the higher HP tune that is in the LLY/LBZ (if that is possible) because we think the only difference between those motors are tuning. So that is my question to you bud, hopefully you know the answer to that, thanks.

Zick

iTrader: (18)

Why doesn't he just put on the normal LMM tune from a 2007+ 3/4 ton pickup? Those are rated slightly higher HP/TQ than the LBZ.

What year is the van that he's pulling the engine from?

gmforlife

iTrader: (2)

I don't know exactly what year, i think around a 2005 or so. Okay, i just didn't know what hp ratings associated with which motor. If it is an LMM motor, i could just go with the newer LMM tune for sure. Thanks for all the help man.

1slow01Z71

iTrader: (36)

Your buddy is wrong. First of all the LMM came out in the 2007.5 NNBS trucks which means he is talking about an LLY if it came out of a 2005 van. And, second the tune for an LMM wont work on an LBZ/LLY because it has all the parameters in it for the DPF system. Now if you edited out the emissions stuff I suppose its a possibility to use that tune but why would you want to when you could just load up a tune with EFiLive that gives you more power and you dont have to mess with the emissions stuff on the LMM tune. Also I would much rather have the Allison since it has 6 gears in the 06+ models which would have alot better acceleration and fuel economy on the highway due to the better O/D ratio.

kbracing96

iTrader: (26)

If it's an 05, there is no way it's an LMM. The LMM is the latest motor from GM and was only sold from about mid 07 to present. 05 will only be a LLY. Now in 06/07, when the LBZ motors came out, there where some motor labeled as LLY motors put in the vans but where really LBZ motor with the LBZ computer (Bosch instead of Delphi) I believe, but detuned because they were in the vans. The LLY's in the vans are are the same motor as in the truck, but with less rated power via the tuning. From what I have read on the dieselplace.com, is that flashing in a truck tune doesn't seem to work very well and causes problems and sometime doesn't run at all. But with software like EFILive, you can just change the fuel and boost tables in the stock tunes and make as much power as you want with the van motor. Stock LLY motor will make more power then either the 4l80 or the Alison can handle

1slow01Z71

iTrader: (36)

Good post both at 4:19